This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section. Abbreviations that may be found in the specification and/or the drawing figures are defined below, after the main part of the detailed description section.
Massive MIMO is a technology where the number of terminals is much less than the number of base station (mobile station) antennas, and has been incorporated into wireless broadband standards like LTE and Wi-Fi. Massive MIMO uses a very large number of service antennas (e.g., hundreds or thousands) that are operated fully coherently and adaptively. Extra antennas help by focusing the transmission and reception of signal energy into ever-smaller regions of space. This brings improvements in throughput and energy efficiency, in particular when combined with simultaneous scheduling of a large number of user equipment (e.g., tens or hundreds).